I wonder if silicon could be used as a substrate
material for a blank?
coefficient of thermal expansion:
soda lime plate glass-.0000089
pyrex 7740 -.0000032
chromium -.0000060
silicon(pure) -.0000030

A friend who worked at a semiconductor plant told me polished silicon has the highest reflectivity of any material known, i have an
ingot "end" about 5" diameter at the base and shaped like a "hershey kiss" i thought about
slicing off a 1" thick piece, and make a mirror
just for the hell of it.
That friend also told me the place he worked at
just throws out the ingot ends and they had them
up to 12"diameter at the time(about 13 years ago) and now over 20"!
I still think pyrex is the best choice of material, but someday something cheaper and better
will undoubtedly be found.

• Re: possible mirror substrate materials? - crockett - February 26, 2001 - 19:16 UTC